How Does Blood Temperature Change During Exercise?

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During exercise, blood carries energy from the body's interior to the surface, where it dissipates heat. A scenario is presented where 0.671 kg of blood releases 1860 J of energy at an initial temperature of 37.0 °C. The discussion focuses on calculating the final temperature of the blood after energy release, using the specific heat capacity of water as a reference. A participant struggles with the calculation, realizing that the final temperature should be found by subtracting the temperature change from the initial temperature. The issue is resolved by correctly applying the formula for temperature change.
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Question:
Blood can carry excess energy from the interior to the surface of the body, where the energy is dispersed in a number of ways. While a person is exercising, 0.671 kg of blood flows to the surface of the body and releases 1860 J of energy. The blood arriving at the surface has the temperature of the body interior, 37.0 °C. Assuming that blood has the same specific heat capacity as water, determine the temperature in degrees Celsius of the blood that leaves the surface and returns to the interior.

Attempt
From the equation:

http://img150.imageshack.us/img150/3461/math052rc5.gif

I get the change in temperature. Since I am given initial temperature all I need to do is take the change in temperature and add the initial temperature:

(change)TEMP = Tf-Ti

Problem:
I'am not getting the right final temp.
 
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The blood at the surface of the body has lower temp. Are you taking the positive value of delta_t and subtracting it from 37?
 
Thanks problem solved.
 
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